1. Field of the Invention
The present invention relates generally to panel inserts for use with structural panels and fasteners having hold out mechanisms. In particular, the present invention relates to panel inserts for use with fasteners having hold out features.
2. Description of Related Art
Grommet inserts, also referred to as panel inserts, for fastening structural panels and composite sandwich panels together are well known in the art. These panel inserts are used in a wide variety of applications, most often as a strengthening means through which a fastener, bolt, or stud nut may be passed to couple other structures to a composite panel. In most cases, these panel inserts are formed by coupling two or more pieces together, usually a male piece and a female piece, through an aperture in the composite panel. There are many different ways to couple the pieces together and prevent them from exerting too much force on the panel, including: press fitting one portion into another, ratcheting one portion into another, receiving the lip of one piece with a groove on the other piece, deformation of one piece by the other piece, and so on. Some of these panel inserts include a counter bore to receive a flush head bolt or stud nut.
Panel inserts generally come in two types: xe2x80x9cprotruding,xe2x80x9d which have flanges that protrude beyond the opposing surfaces of the panels, and xe2x80x9cflush,xe2x80x9d which have flanges that are flush with one or both of the opposing exterior surfaces of the panel. Flush panel inserts usually involve some inward deformation of the panel surfaces near the aperture that passes through the panel. Although protruding panel inserts do not require any deformation of the panel, the flanges of the protruding panel insert often get in the way when panels or parts are being assembled or disassembled, particularly when bolts or stud nuts passing through the grommet also protrude beyond the surfaces of the panel. On the other hand, because the flanges of flush panel inserts are flush with one or more of the opposing surfaces of the panel, the panels assemble and disassemble easier and faster, with less opportunity for incidental damage from handling.
The primary purpose of these grommet panel inserts is to strengthen the panel at aperture through which the fastener, bolt, or stud nut passes.
Although these flush panel inserts may be installed flush with the exterior surfaces of the structural or composite panel, they do not adequately provide for flushly mounting fasteners having hold out mechanisms.
There is a need for a composite panel insert having a recess to receive a hold out mechanism of a fastener or stud nut, whereby the hold out mechanism and the stud nut are flush with a surface of the composite panel when the stud nut is in a hold out position.
It is an object of the present invention to provide a composite panel insert having a recess to receive a hold out mechanism of a fastener or stud nut, whereby the hold out mechanism and the stud nut are flush with a surface of the composite panel when the stud nut is in a hold out position.
A principle advantage of the present invention is that when the hold out mechanism and the stud nut are flush, or sub-flush, with the interior surface of the composite panel, i.e., the surface of the panel that mates with another structural component, ease and speed of assembling and disassembling other parts and panels to the composite panel is greatly improved. Another advantage of the present invention is that incidental damage from handling to the composite panel and other parts and panels is reduced because fewer studs and nuts protrude out from the exterior surface of the composite panel.
The above, as well as, additional objects, features, and advantages of the present invention will become apparent in the following detailed description.